The overall aim of this proposed project is to assess the outcomes and professional alcoholism treatment cost offset of Alcoholics Anonymous (AA), which is the source of help most frequently sought by individuals with drinking problems. Despite AA's size, substantial influence on the professional treatment system, and potential for public health impact, few rigorous evaluations of its effectiveness have been conducted. Prospective, longitudinal studies could evaluate the drinking-related and psychosocial outcomes of AA participation, and determine whether AA participation results in reductions or increases in professional treatment service utilization and attendant costs. The aims of this project will be pursued by conducting secondary analyses of an existing eight-year longitudinal data set drawn from a previous study of 631 individuals with drinking problems. In the initial study, participants were recruited at public detoxification facilities and alcoholism information and referral services. Information on drinking variables (e.g., alcohol consumption, symptoms of dependence), psychosocial functioning (e.g., coping responses, quality of relationships with others), treatment utilization, and AA participation were gathered at initial contact, and also one, three and eight years afterwards. Using two statistical techniques that help control for self-selection effects (Heckman's sample selection model approach and hierarchical multiple regression), analyses of the eight-year data set will be conducted to evaluate whether individuals who attended AA had better outcomes on drinking related and psychosocial variables than did individuals who sought either professional treatment, or no help of any form. For the costs offset analysis, the total cost (in 1994 constant dollars) of all professional alcoholism treatment services utilized by participants over the eight-year period will be calculated. The effect of AA participation on treatment costs will then be estimated, to determine if AA reduces or increases costs in the professional alcoholism treatment sector.